expressed concern over the ability of foreign hackers to compromise critical american infrastructure the pentagon is planning a range of defensive measures including a massive expansion of its own signer security force. joining me to discuss the developing background is david sanger of the "new york times." he cowrote today's front page story on the subject. joining us later is dune lawrence of bloomberg businessweek if and michael riley of bloomberg. they are learning everything they could. >> so far it's clear they've been into those systems it's not clear they've ever done anything to them. >> rose: why -- >> that's the remarkable question charlie. always the issue is intent and the degree to which the political leadership in china actually is knowledgeable about this and to what degree of control it has over it. because chinese command and control is not always what we image it from afar. in this case, unit 61398 which is the major cyber intelligence unit for the pla but not their own cyber operation. sort of their equivalent of the national security agency or our cyber command which is locat